1. Technical Field
The present invention relates to semiconductor circuits in general, and in particular to silicon on insulator semiconductor circuits. Still more particularly, the present invention relates to a silicon on insulator domino logic circuit.
2. Description of the Prior Art
Domino logic circuits are commonly found in integrated circuits. A domino logic circuit simplifies digital logic by connecting a number of transistors together in series to implement digital combination logic. For example, a domino logic circuit implements a logic AND function by simply cascading a p-channel transistor with several n-channel input transistors in series. During operation, the p-channel transistor is clocked to precharge an output node of the circuit to a predetermined logic state. Depending on the logic state at the inputs of the n-channel input transistors, the output node either remains at its precharged state or is pulled low through the series of n-channel input transistors by a clocked n-channel transistor connected to ground.
In recent years, the predominant processing technology for integrated circuits has been the complementary metal oxide silicon (CMOS) technology. Although CMOS technology offers various advantages, such as low power consumption and stability, over other types of processing technologies, one major drawback of CMOS domino logic circuits is the effect of charge sharing. The present disclosure describes an improved domino logic circuit that is implemented with a so-called silicon on insulator (SOI) technology. A detailed description of the SOI technology can be found in Weste and Eshraghian, Principles of CMOS VLSI Design: A Systems Perspective, 2nd ed., pp. 125-130, Addison Wesley (1995), the pertinent portion of which is incorporated herein by reference. Instead of using silicon as a substrate like the CMOS technology, SOI utilizes an insulating substrate, which provides tremendous improvements in certain process characteristics, such as latch-up and speed, over the CMOS technology. In addition to overcoming the problem of charge sharing, the improved domino logic circuit is also able to generate an output signal faster than a conventional CMOS domino logic circuit.